Reserve dyeing on vegetable fibers



Patented Aug. 7, 1928.

UNITED. STATES PATENT OFFICE.

HANS LEEHANN, OF BOTTHINGEBHUHLE-BINNINGEN, NEAR BASEL, AND GIOVANNI TAGLIANI, OF BASEL, SWITZERLAND, ASSIGNORS, BY MESNE ASSIGNMENTS, TO IUNITEX CORPORATION, OF LODI, NEW JERSEY, A CORPORATION OF NEW JERSEY.

RESERVE DYEING N VEGETABLE FIBERS.

No Drawing. Original application filed April 27, 1925, Serial No. 26,289, and in Germany May 7, 1924. Divided and this application filed May 20, 1926. Serial No. 110,589.

This application is divisional of application Ser. No. 26,289. g

The hitherto known reserve processes consist of mechanical or chemical operations. 6 To the first type belongs the bmdmg and covering of the vegetable fibers (yarns and fabrics) b substances insoluble 1n water so that the gyestufi's employed can only soak in and be fixed on the unbound or uncovered 1 parts of the fabric. To the second class belongs the application of certain agents, preferably of salts, which react chemically during the dyeing or during the development of the dyes. All these processes depend,

' however, on certain conditions. If the re serve agents employed are removed during the dyeing process or during the development of the dyes, or if the do not'resist these operations until the en of the dyemg, then the desired reserve effect does not occur and the fabric i dyed uniformly throughout as if the reserving agents had not been used at all.

It is known from German specification No. 346,883 and others, that it is possible to render vegetable fibers (yarns, loose mate rial, fabrics) comipletely immune against substantive dyestu s by treating them after alkalinization with solutions of aromatic so acid chlorides or aromatic sulpho acid ch10- rides. Both the alkalinization and the action of the aromatic carboxylic acid or sulpho acid chlorides are so effected that the whole of the vegetable fibers is brought into the solutions of the respective agents.

It has now been shown in a surprising manner that this esterification can also be used for the topical alteration of the vegetable fibers, in view of the production of reserve eflects, for example in a suitable printing process. It was not at all to be foreseen from the more active treatment in solution that the short superficial and sparing local treatment, as it takes place for example in the printing process, would sufiice to produce the desired esterification. This process affords permanently reserving patterns with unexpected dyeing properties, which remain fast even after hot washing 0 erations, after hot neutral, acid or alkaline ye baths.

The production of such reserve effects is now utilized in the process for reserve dyeing on vegetable fibers forming the subject of the present invention. This process consists in first treating topically the vegetable fibers by a local printing with a suitable alkalizing agent, such for example as a concentrated alkaline solution, with or without thickening agent, with or without the addition of alcohol, with or without an alcoholic solution of an alkali alcoholate, then in ap-' plying thereon in dry or moist condition, an esterifying aromatic acid chloride, such as an aromatic carboxylic acid chloride, or an aromatic sulpho acid chloride, in pure or dissolved condition, and finally after the resulting esterification, in thoroughly washing the vegetable fibers being thus locally altered at the place of the aforesaid print, to constitute what is commonly termed as reserve efiects. Thereupon the thus topically altered fibers are dyed in one single bath with both a substantive and a convenient acid dyestufi. The substantive dyestutf is fixed by the unaltered parts, while the acid one dyes the esterified parts of the fibers.

As dyestufi's, there may be used the usual coloring matters which are suitable for carrying out the improved process. The fibers may be in form of loose material, yarns or fabrics.

What we claim is:

1. A process for reserve dyeing on vegetable fabrics, which consist in treating topically the vegetable fibers by a local printing with an alkalizing agent, thereupon applying an esterffying aroma-tic acid chloride to produce a topical alteration of the locall rinted fiber, thus constituting reserve e 'ects, then washin after the esterification, and thereupon dyeing the thus topically altered fibers in one single bath with both a substantive and a convenient acid dyestufl'.

2. A process for reserve dyeing on vegetable fibers, which consists in treating topically the vegetable fibers by a local printing with an alkalizingagent, thereupon applying an esterifying aromatic sulphoacid chloride to produce a topical alteration of the locall printed fiber, thus constituting reserve e ects, then washing after the esterification, and thereupon dyeing the thus topically altered fibers in one single bath with both a substantive and a convenient acid dyestufi.

3. A process for reserve dyeing on vegekalizing agent, esterifying said treat/ed areas with an aromatic sulpho acid chloride whereby reserve efi'ects are produced, washing said fibers and dyeing the thus treated areas in a bath containing both a substantive and an acid dyestuff.

In witness whereof we have hereunto signed our names this 10th day of May,

HANS LEEMANN. GIOVANNI TAGLIANI. 

